The present invention relates to materials for use as articular surfaces of prosthetic joint components. More particularly, it relates to reinforced polyethylene for articular surfaces.
Researchers have developed prosthetic joint replacements for all of the major skeletal joints of the human body. These prosthetic joints are used to replace degenerating or traumatized joints and thereby reduce pain and restore function. Most prosthetic joints currently available comprise a biologically compatible metal such as Ti--6Al--4V alloy or Cobalt-Chromium-Molybdenum alloy on one side of the joint and ultra high molecular weight polyethylene (UHMWPE) on the opposing side. The combination of metal and UHMWPE works well as a low friction articulating pair. However, there has been some concern over the biocompatability of fine particles of UHMWPE wear debris. This has led researchers to investigate ways of reducing the wear debris generated by metal on UHMWPE articulation while continuing to take advantage of the low friction and biocompatibility of bulk UHMWPE. In addition, UHMWPE will deform under load in a process known as cold flow. It is therefore desirable to control cold flow in order to provide dimensional stability and prevent the thinning of articular components to the point of breakage or wear through.